From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751197AbZDLQfJ (ORCPT ); Sun, 12 Apr 2009 12:35:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750745AbZDLQez (ORCPT ); Sun, 12 Apr 2009 12:34:55 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:55101 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750730AbZDLQey (ORCPT ); Sun, 12 Apr 2009 12:34:54 -0400 Date: Sun, 12 Apr 2009 18:33:56 +0200 From: Ingo Molnar To: Linus Torvalds Cc: "H. Peter Anvin" , Avi Kivity , Pavel Machek , mingo@redhat.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, hpa@linux.intel.com, rjw@sisk.pl, linux-tip-commits@vger.kernel.org Subject: Re: [tip:x86/setup] x86, setup: "glove box" BIOS calls -- infrastructure Message-ID: <20090412163356.GA2392@elte.hu> References: <49DE7F79.4030106@zytor.com> <20090410080444.GC16512@elf.ucw.cz> <20090410103934.GA21506@elte.hu> <20090410104648.GA31516@elf.ucw.cz> <20090410112546.GD21506@elte.hu> <20090410113824.GA18823@elf.ucw.cz> <49E0C1AB.2050608@redhat.com> <49E17A6E.5000104@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Linus Torvalds wrote: > Sure, go ahead and wrap them in some kind of "save and restore all > registers" wrapping, but nothing fancier than that. It would just > be overkill, and likely to break more than it fixes. Yeah. I only brought up the virtualization thing as a hypothetical: "if" corrupting the main OS ever became a widespread problem. Then i made the argument that this is unlikely to happen, because Windows will be affected by it just as much. (while register state corruptions might go unnoticed much more easily, just via the random call-environment clobbering of registers by Windows itself.) The only case where i could see virtualization to be useful is the low memory RAM corruption pattern that some people have observed. The problem with it, it happens on s2ram transitions, and that is driven by SMM mainly - which is a hypervisor sitting on top of all the other would-be-hypervisors and thus not virtualizable. Which leaves us without a single practical case. So it's not going to happen. Ingo